[SOLVED] Correct resolution displays incorrectly on monitor

kyomi · 2021-12-16 13:27:29

Hi! First of all, I'll give you guys as much detail as possible for you to get the full context of my issue, as they might interfere with the final issue.
Hang in there for a while before I actually get to trouble.

I have an NVIDIA GT 630 graphics card installed in my computer. Following the guidelines of the official NVIDIA website, theoretically I could install the video driver 451.67, however, one thing that was not explained on the website (and it took me a long time to really understand) is that the architecture of my video card is different (Fermi architecture), and this particular architecture no longer receives updates from NVIDIA. Because of this I can only install video drivers up to version 391.35, which NVIDIA didn't even bother to adapt for Linux.
With that in mind, the only driver I can install is nvidia-390xx-dkms, which it adapts to driver version 390.144 (see: NVIDIA#Installation).

The second part of the problem is that, even installing the drivers correctly, Linux did not provide the correct resolution for the monitor (1360x768). To fix this, I used the nvidia-xconfig command along with xrandr#Permanently adding undetected resolutions to permanently add the undetected resolution and it worked correctly, the resolution was added.

And finally, the real problem: when using this resolution, the screen is a little "flattened" leaving black borders on the left and right sides. I tried to search a lot but I couldn't find anything about it. Using slightly smaller resolutions like 1280x720 does not cause this flatness and taking a screenshot of the entire screen appears as if the image had the resolution 1360x768 (that is, the correct resolution).

Is there any solution for this?

Useful informations:
- "xrandr" command output: https://mystb.in/SubsequentlyDeviationCredits.apache
- "cat /etc/X11/xorg.conf.d/10-monitor.conf" command output: https://mystb.in/StakeBuildersMarriage.apache

If you need more information, please feel free to ask.

Last edited by kyomi (2021-12-20 17:38:11)

seth · 2021-12-16 16:49:20

If you need more information, please feel free to ask.

Vendor/model of the attached monitor and your xorg log, https://wiki.archlinux.org/title/Xorg#General
xrandr has XGA as the default resolution what smells like you end up running the VESA driver (or the monitor doesn't provide a useful EDID)

kyomi · 2021-12-16 18:21:10

Hi, seth! Thank you for the response and for your dedication to helping.

My monitor is a bit old too. It's a Samsung 933SN PLUS, you can find more information of this monitor easily on Google.
I uploaded my Xorg logs to MystBin: https://mystb.in/LindaOmanExercises.yaml.

Thank you again.

Last edited by kyomi (2021-12-16 19:05:07)

seth · 2021-12-16 20:50:39

You're running the nvidia driver and there's no EDID…
Does "little flattened" mean you see the full image, but it's squeezed into a 4:3 aspect? Nothing is cut off?
If so, try to play w/ the screens OSD settings, in particular Size&Position/Image Size - there "PC Signals" and "AV Signals" and you can force it to be wide/16:9

kyomi · 2021-12-16 21:46:15

Hi seth. Thanks for the answer.

seth wrote:

You're running the nvidia driver and there's no EDID…
Does "little flattened" mean you see the full image, but it's squeezed into a 4:3 aspect? Nothing is cut off?
If so, try to play w/ the screens OSD settings, in particular Size&Position/Image Size - there "PC Signals" and "AV Signals" and you can force it to be wide/16:9

I just found out something really weird, but first, to answer your question: no, nothing is being cut, and it doesn't look 4:3 either. Here's a picture of how it's getting:
https://cdn.discordapp.com/attachments/ … G_2300.jpg

About the option "Size & Position/Image Size" on the monitor, if I set it to "Wide", the display is stretched, but one thing I noticed was in the "Information" tab, it shows that I'm using the resolution 1280x768 (while the computer shows 1360x768), and this left me quite confused. I don't understand why the monitor is using a different resolution than what it was "ordered" to use.

Edit: Didn't know the picture would get so big, sorry about that. Currently the option "Size & Position/Image Size" is set to "Auto" and there are no other options besides these.

Last edited by kyomi (2021-12-19 23:14:30)

seth · 2021-12-16 22:22:13

Please remove the picture and just post the link to it (the board has a 250x250 max rule)
The specs in the manual suggest "1360 X 768 / 47.712KHz / 60.000 Hz / 85.500 pclk / +/+" which is different from the cvt generated modeline (certainly the polarity but also some other values are slightly off)
You could use https://archlinux.org/packages/extra/x8 … -xvidtune/ to adjust the mode until the output detects it as "its" 1360x768.

kyomi · 2021-12-19 23:31:02

seth wrote:

Please remove the picture and just post the link to it (the board has a 250x250 max rule)
The specs in the manual suggest "1360 X 768 / 47.712KHz / 60.000 Hz / 85.500 pclk / +/+" which is different from the cvt generated modeline (certainly the polarity but also some other values are slightly off)
You could use https://archlinux.org/packages/extra/x8 … -xvidtune/ to adjust the mode until the output detects it as "its" 1360x768.

Hi, sorry for the delay in replying.

I just tested this tool and I can't use it properly (I'm probably using it wrong). When trying to make the screen wider and clicking on "Apply" an error appears saying "You have requested a mode-line that is not possible, or not supported by your hardware configuration".

I believe that to make it the right size, I must put an exact and correct mode-line, since my monitor doesn't support any mode-line, however, I don't have much knowledge in this tool. I will try to find the correct mode-line, if you have any tips on how to find it, please let me know.

Thank you again.

seth · 2021-12-20 08:08:29

It might be sufficient to have

Modeline "1360x768_60.00"  84.75  1360 1432 1568 1776  768 771 776 798 +hsync +vsync

which is the standard cvt12 calculation (slightly different from the cvt calculation) but notably w/ "+hsync" instead of "-hsync", which is the significant deviation from the monitor specs.
Ttry adding and setting the mode w/ xrandr - not your xorg.conf in case this leaves you w/o any output at all!

kyomi · 2021-12-20 17:37:11

seth wrote:

It might be sufficient to have
Modeline "1360x768_60.00"  84.75  1360 1432 1568 1776  768 771 776 798 +hsync +vsync
which is the standard cvt12 calculation (slightly different from the cvt calculation) but notably w/ "+hsync" instead of "-hsync", which is the significant deviation from the monitor specs.
Ttry adding and setting the mode w/ xrandr - not your xorg.conf in case this leaves you w/o any output at all!

Hi, thanks for the help, now the monitor is showing the resolution correctly. This saved me weeks of research and headaches. You are the best!
Marking this thread as solved.

Arch Linux

#1 2021-12-16 13:27:29

[SOLVED] Correct resolution displays incorrectly on monitor

#2 2021-12-16 16:49:20

Re: [SOLVED] Correct resolution displays incorrectly on monitor

#3 2021-12-16 18:21:10

Re: [SOLVED] Correct resolution displays incorrectly on monitor

#4 2021-12-16 20:50:39

Re: [SOLVED] Correct resolution displays incorrectly on monitor

#5 2021-12-16 21:46:15

Re: [SOLVED] Correct resolution displays incorrectly on monitor

#6 2021-12-16 22:22:13

Re: [SOLVED] Correct resolution displays incorrectly on monitor

#7 2021-12-19 23:31:02

Re: [SOLVED] Correct resolution displays incorrectly on monitor

#8 2021-12-20 08:08:29

Re: [SOLVED] Correct resolution displays incorrectly on monitor

#9 2021-12-20 17:37:11

Re: [SOLVED] Correct resolution displays incorrectly on monitor

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